Method and means for coating cores



Jan. 25,1927.

H. G. WALKER ET AL METHOD AND MEANS FOR COATING CORES Filed June 20, 1922 Patented Jan. 25, 1927.

' UNITED STATES PATENT GFFlQE,

nownnn enonen WALK R, or BERWYN, Ann ALBERT THOMAS Manon, on CHICAGO, ILLmoIs, AssIenons T0 wns'rnnn ELECTRIC COMPANY, moonronarnn, on NEW YORK, N. Y., A CORPORATION on NEW YORK.

METHOD AND MEANS FOR COATING CORES.

Application filed .Tune 20,

This invention relates to a coated core and method of coating the same.

The object of the invention is to produce a core having a cdating of pulp thereon which is attached to the core solely by an intermingling of the fibres thereof and without the use of any adhesive material, the said coating being smooth, and uniform, and conforming with the contour of the core;

The present method may be employed to advantage for insulating electrical conductors. but it is to be understood that it is not limited to this purpose but only in so far as is defined by the appended claims. Where the method is used for insulating electrical conductors, manila, wood, rag, cotton, esparto, jute, hemp, and asbestos pulps may be employed as the coating material, but other materials than those specified may be used without departing from the spirit and scope of the present invention.

The term core in strand form as used in the specification and appended claims refers to a core having a configuration resembling a fibre, hair, filament, string, small cord or the like, or it may be in the nature of a rope consisting of fibres, yarns or wires twisted together. i

The drawings illustrate the method 'as employed for coating a core in strand form, the steps oatthe method consisting in first bringing the core to be coated into intimate contact with a liquid containing pulp in a manner such that pulp is applied thereto; second, removihg the core from the pulp mixture to permit the deposited pulp to cling tothe core; third, removing the excess moisture from the pulp without detaching it from the core; fourth, forming the pulp while still moist. so that it-cont'orms with the shape of the core; fifth, removing all or .a definite part of the moisture "from the pulp coating; and sixth, smpothing the coating preferably in the presence of heat and pressure to make it uniform and tree from ridges, abrasions and the like.

Where it is desired to give the coating :1 surface so smooth that it may be said to be polished, a suitable sizing such as a rosin r 'mixtlire may be added to the liquid containing the pulp, orthe formed pulp on the core either dry or partially dry may be passed through a sizing solution so as to cause it 1922. Serial in. 569,755.

to absorb some of the sizing material and when the coating is subjected to the last step .of the processin the presence of heat, the

cation and claims is to be understood as Fig. 2 is an enlarged top plan fragmentary view of a portion of the apparatus shown in Fig. 1;

Fig. 3 is an enlarged vertical sectional view taken on the line 3-3 of Fig. 2, and,

Figs. 4, 5, 6, and 7 are enlarged views showing the form of the pulp coating on the core as it is delivered from'the liquid containing pulp, the squeezing rolls, and former respectively.

Referring now to the drawings in detail, in which like reference numerals designate similar parts throughout the several views,

the core to be coated is fed from a supply 20, over an idler roll 21, and thence around a.

drum 22 which is partly submerged in a liquid containing pulp within a semispherical trough 23. The drum comprises a pair of sheet metal sides and a peripheral portion which is provided with a plurality of large perforations (not shown) which are covered with a narrow strip of fine wire mesh 27. The core in passing "around the drum lies upon the wire mesh 27 as shown in Fig. 2. 'The drum 22 has a centrally disposed tubular axle 28 which is rotatably mounted in suitable bearings 29 carried by :a framework 30 which supports all of the elements of the apparatus.

In order to apply pulp to the core as it passes over the drum 22, the liquid within the drum is maintained at a lower level than that of the pulp mixture in the tank 23, as indicated by the dotted lines A and B re spectivbly. This difierence in levels is maintained bya siphon pipe 31 which has its inlet opening submerged in the liquid Within the drum 22 and its discharge through the tubular axle 28. A continuous circulation of the pulp mixture is maintained in the tank 23 by feeding the pulp mixture from a supply tank 32 into the tank 23 and out of the said tank through a pipe 19 into a receiving tank (not shown) from which it is pumped back into the supply tank 32- in any suitable manner. As the drum 22 carries the core thereon through the tank, due to the difference in the levels of the liquid within the drum and the tank 23, the liquid in the tank 23 will pass through the wire mesh 27, straining the pulp onto the other surface of the wire mesh, and applying pulp on the core supported thereon. In prder to keep the wire mesh clean prior to its reception of the core and a new coating of pulp, it is washed by a jet of water under pressure which is supplied through a nozzle 33.

The drum is rotated in the direction indicated by the arrows. The core with the coating of pulp thereon leaves the drum at the top thereof, and the force of gravity, surface tension of the liquid in the pulp mixture, and the felting action of the pulp fibres cause it to surround the core and cling to it in substantially the form shown in Fig. 4.

From the drum 22 the core with pulp applied thereon is passed over an auxiliary roll 34 and then between a pair of squeezing rolls 35 and 36. These rolls are rotatably mounted between a pair of brackets 37, secured to an upright standard 38 supported by the framework 30. The shaft carrying the roll 36 is driven b any suitable means (not shown). The ro ls 35 and 36 preferably draw the core from the supply roll 20, over the drum 22, causing it to rotate and then between them.

The auxiliary roll 34, as shown in Fig. 2, is a hollow sheet metal drum having a eripheral slot covered with a. strip of ne wire mesh 42. It has been found preferable to employ the auxiliary roll 34 and to make it foraminous where it engages the core and pulp coating thereon in order that the free liquid, so to speak, may be strained ofi away from the core and coating Without causing a back flow of the liquid which would tend to wash off the pulp coating which at this stage of the process is very soft and moist and easily removed from the core. With the free liquid removed the coating has greater strength, due to a closer felting of the fibres so that when the core and coating are passed throughthe squeezing rolls the coating will not be tbrn from the core.

The squeezing rolls may be formed of rubber and forced together by any suitable ten sion means which is adjustable to present the proper pressure on the core and pulp coating as they pass between the rolls. These rolls remove the greater portion of the liquid from the pulp mixture and form the pulp into a thin ribbon which extends laterally from each side of the core as is shown in Fig. 5. This squeezing operation also tends to mat or felt the fibres into more intimate relation, increase the tensile strength of the covering and secure it to the core.

From the squeezing rolls the core wit-h its ribbon pulp coating is drawn through a former which wraps the projecting edges of the ribbon around the core and around each other, the appearance of the coating after it is first acted on by the former and after the forming action is completed being shown clearly in Figs. 6 and 7. The former causes a thorough intermingling of the pulp fibres and shapes the coating so that it embraces the core and conforms to the shape thereof.

The former comprises two cup-shaped collars 43 and 44 held together and in spaced relation by means of rods 45, Figs. 2 and 3. Integral with each of said collars 43 and 44 is a sleeve 46 and 46' respectively which are rotatably mounted within suitable hearings in the standards 37 and another pair of standards 47 which are supported by the framework 30. Two plates 48 and 49 have projecting tongues which are bentaround two of the rods to pivotally support the plates in opposed relation to each other. Gompression springs 50 engage the rear faces of each of the plates 48 and 49 and tend to force them together. The springs 50 are put under the requisite tension by means of adjusting screws 51. The ends of the plates 49 and 50 adjacent the squeezing rolls 35 and 36 are flared outwardly so as to present a smooth surface to the core and pulp coating as they pass from the said rolls through the sleeve 46 and between the forming plates 48 and49. The core passes from the forming plates through the sleeve 46.

The forming plates 48 and 49 are rapidly rotated around the core and pulp coating through the medium of a pulley 18 secured to the sleeve 46 the pulley being driven by any suitable means (not shown). The forming plates 48 and 49 wrap the projecting edges of the pulp ribbon around each other and around the core in much the same manner as though the core and pulp ribbon were rolled on a table top with the palm of the hand.

The core with its formed coating is drawn from the former and subjected to a mechanism for drying the coating to the desired nun degree. The means shown for drying the coating are a pair of wide hollow drums 52 and 53 heated internally and having a plurality of grooves formed thereon not shown), guides (not shown) being provided for directing the core over first one drum and then the other until it has traversed all of the grooves on both drums. The drums 52 and 53 are revolvably mounted in suitable bearings carried by vertical standards supported by the framework and are driven by suitable means (not shown).

For a detailed description and illustration of the apparatus heretofore described reference is made to our co-pending application Serial No. 547,924. filed March 29, 1922, since this apparatus is identical to that shown in the application above referred to.

From the drums 52 and 53 the coated core is passed through a second forming mechanism which is identical with the former previously described andshown in detail in Figs. 2 and 3. The former 60, however, is mounted within an oven 61 heated by any suitable means such as burner 62. The oven and burner are supported on standards 63 carried by the framework 30.

In some cases it may be found desirable to thoroughly dry the coating on the drums 52 and 53 and then add to the coating the required amount of moisture by a spray 75 or other suitable means, before the coated core is subjected to the former 60. When the coated core reachesthe former 60 it conforms substantially with the shape of the core and the former 60 serves to smooth or iron the coating so that it is uniform, even, smooth, and free from all ridges, abrasions or the like. tuted for the former 60 such as rolls, die or dies, etc., without departing from the spirit and scope of the present invention.

From the former 60, the coated core is stored on a take-up reel 54 rotatably mounted in bearings supported by spaced brackets carried by the framework 30 the reel being driven by any suitable means (not shown). a i

W here it is desired to give the pulp coating a surface so smooth that it may be said tobe polished suitable sizing such as a rosin mixture may be added to the liquid containing pulp or to the artia'lly or fully dried coating on the contuctor and when the coating is acted upon by the heated former (30 the surface of the coating will be polished or ironed and given a finish much like that given sized super-calendered or coated paper when passed through the calendering rolls of a paper machine or the rolls of a super-calender.

What is claimed is:

1. A method of coating a core in strand form consisting in subjecting the core to a liquid containing pulp in such manner that Various other means may be substipulp is applied thereto, so treatin the pulp that it conforms with the shape 0 t the core, and then so treating the said pulp that it constitutes a smooth, even and uniform coatmg.

2. A method of coating a core in strand form consisting in subjecting the core to a liquid containing pulp in such manner that pulp is applied thereto, so treatin the pulp that it conforms with the shape 0 the core, and then so treating the said pulp in the presence of heat and pressure that it constitutes a smooth, even, and uniform coating.

3. A method of coating a core consisting in subjecting the core to a li uid. containing pulp and a sizing material in such manner that pulp is applied to the core and then so treating the pulp that it constitutes a smooth, even, and uniform coating.

4. A method of coating a core in strand form consisting in subjecting the core to. a

liquid containing pulp in such manner that pulp is applied thereto, drying the pulp on the core and then so treating the said pulp in the presence of heat and pressure that it constitutes a smooth, even, and uniform coating.

5. A method of coating a core in strand form consisting in subjecting the core to a liquid containing pulp and a sizing material taining pulp mixture to a core to cause it to cling thereto in ribbon form, wrapping the ribbon laterally around the core, and then so treating the said pulp that it constitutes a smooth, even, and uniform coating.

7. A method of coating a core consisting in subjecting the core to apulp in such manner that pulp is applied thereto, squeezing" the core and the pulp thereon so that the said pulp forms a ribbon extending to opposite sides of the core, so treating the pulp as to make it conform with the core and then so treating the said pulp that it constitutes a smooth, even, and uniform coating.

8. A method of coating :1 core consistin in subjecting the core to a pulp in such manner that pulp is applied thereto, so treating the pulp that it conforms with the core, drying the pulp on the core, subsequently moistening the said pulp, and then so treating the pulp in the presence of heat and pressure that it constitutes a smooth, even and uniform coating. 9. A method of coating :1 core consistin in subjecting the core to a pulp and a sized material in such manner that a sized pulp coating is formed on thefcore, thoroughly iltl drying the. pulp on the core, subsequently moistening the said pulp, and then so treating the pulp in the presence of heat and pressure that is constitutes a smooth, even and uniform coating.

10. A method of coating a core, consisting in subjecting the core to a pulp" in such manner that pulp is applied thereto, so treating the pulp that it conforms with the core, drying the pulp on the core, subsequently applying a sizing material to the pulp, and then so treating the pulp in the presence of heat and pressure that it constitutes a smooth, even, and uniform coating. 11. A method of coating a core, consisting 1n applying llqllld contamng pulp to the core, causing it to cling thereto in ribbon form, removing excess moisture from the ribbon, wrapping the ribbon laterally around the core to cause an intermin *ling of the fibres thereof, and then so treatmg the pulp in the presence of heat and pressure that it constitutes a smooth, even, and uniform coating.

12. A method of coating a' traveling core in strand form, consisting in subjecting the core while it is in motion to pulp in such manner that the pulp is applied thereto, so treating the pulp that it is attached to the core by a felting of the pulp fibers, and then so treating the pulp that it constitutes a smooth, even, ant uniform coating.

13. A method of coating a traveling core in strand form, consisting in subjecting the core while it is in motion to a liquid containing pulp in such manner that pulp is applied thereto, so treating the pulp that it conforms with the core, and then so treating the pulp with a sizing material that it constitutes a smooth, even, and uniform coating. I 14. A method of coating a traveling core in strand form, consisting in subject ng the core while it is in motion to a iqiud containing pulp in such manner that pulp is applied thereto, so treating the pulp that it conforms with the core, and then so treating the pulp in the presence of heat and pressure that it constitutes a smooth, even, and uniform coating.

- 15. A method of coating a traveling core in strand form, consisting in subjecting the core while it is in motion to a liquid conmanner that pulp is applied thereto, treating the pulp in a manner such that it is attached to the core by the felting of the pulp fibres and has a curved outer contour, and then treating the pulp so that it constitutes a smooth, even and. uniform coating.

16. A. method of coating a core in strand form, consisting in applying unfinished paper to the core retained on thecore by felting of the pulp fibers, subsequently completing the fabrication of the unfinished paper on the core, and then so treating the form coatin 17. A met 0d of coating a traveling core in strand form, consisting in subjecting the core While it is in motion to a liquid containing pulp in such manner that pulp is applied thereto, forming the pulp on the core so that it has a substantially circular outer surface, and treating the pulp on the core with a sizing material so that it constitutes a smooth, even and uniform coating.

18. A method of coating a core in strand form with pulp, consisting in forming the pulp around the core to cause it to be attached thereto by an intermingling of the fibres thereof, and then so treating the pulp that it constitutes a smooth, even, and uniform coating.

19. A method of coating a core in strand form with pulp, consisting in subjecting the core to a liquid containing pulp in such manner as to apply said pul in the form of a ribbon longitudinally of t e core, Wrapping the ribbon laterally around the core, and then so treating the ribbon that it constitutes a smooth, even, and uniform coatmg. l

20. A method of coating a core in strand form with pulp, consisting in subjecting the core to a liquid containing pulp in such manner as to apply said pulp in the form of a ribbon longitudinally of the core, wrapping the 'ribbon laterally around the core, and then so treating the ribbon with a sizing material that it constitutes a smooth, even, and uniform coating.

21. In a machine for coating a core in strand form, means for applying pulp to the core so that the pulp is attached thereto by a felting of the pulp fibers, means for treating the pulp so that it conforms with the core, and pressure means for treating the pulp so that it constitutes a smooth, even, and uniform coating for the core.

22. In a machine for coating a core in strand form, means for applying pulp to the core, means for imparting a contour to the pulp substantially like that of the core,

means for mechanically polishing the pulp so that it constitutes a smooth, even, and uniform coating, and means for heating the last-mentioned means.

23. In a machine for coating a core in strand form with pulp, means for applying pulp to the core, means for wrapping the pulp around the core to cause an intermin gling of the fibres thereof, and means engaging the pulp for working the pulp into a smooth, even, and uniform coating for the pulp around the core to cause an interminstrand form with pulp,

gling of the fibres thereof, meansengaging the pulp for working the pulp into a smooth, even, and uniform coating for the core, and means for applying asizing material to the pulp.

25. In a machine for coating a core in strand form with pulp, means for applying pulp to the core, rotary nieansfor imparting a contour to the pulp substantially like that of thecore, and a second means rotatable about the core for polishing the pulp.

26. In a machine for coating 2. core in means for applying a liquid containing pulp to the core, means for removing excess moisture fromthe pulp, means for wrapping the pulp around the core to cause an intermingling of the fibres thereof, and separate means for mechani cally polishing the pulp so that it constitutes a smooth, even, and uniform coating for the core.

27. In a machine for coating a core in strand form with pulp, means for applying a liquid containing pulp to the core,means for removing excess moisture from the pulp, means for wrapping the pulp around the core to cause an intermingling of the fibres thereof, means for applying a sizing material to the pulp, and separate means for mechanically polishing the pulp so that it constitutes a smooth, even, and .uniform coatin for the core.

a machine for coating a core in strand form with pulp, means for applying pulp in ribbon form to the core, means for wrapping the ribbon laterally around the core, and means rotating about said core as an axis for working the pulp into a smooth, even, core. a

29. In a machine for coating a core in and uniform coating for the strand form with pulp, means comprising a rotatable recqptacle holding a liquid containing pulp or applying pulp to the core, means for rotating the receptacle, means for imparting a, contour to the pulp substantially like that of the core, and separate means engaging the pulp for workin the pulp into a smooth, even, and uniform coatin for the core.

30. n a machine for coating a core in strand form with pulp, means for applying liquid to the core containing pulp, means for removing excess moisture from the core, rotary meansifor imparting a contour to the pulp substantially like that of the core, means for applying a sizing material to the pulp, means for mechanically working the pulp into a smooth, even, and uniform coating for thecore, and means for heating the last-mentioned means.

In witness whereof, We hereunto subscribe our names this 13 day of June A; D., 1922.

HOWARD GEORGE WALKER. ALBERT THOMAS MARCH. 

